Retractable sample scoop and method

ABSTRACT

A retractable sample scoop is shown that is mountable to a pipeline for taking samples from the pipeline. A retractable mounting mechanism mounts to the pipeline wall. A tubular is extendable into the opening of pipeline and retractable from the pipeline. A first seal creates sealing around the tubular portion with respect to said pipeline while permitting insertion, retraction and rotation of said first tubular portion with respect to said pipeline. A second seal comprises a tubular without threads to pipe connector with threads.

This application claims benefit of U.S. Provisional Patent Application No. 61/769,896 filed Feb. 27, 2013.

CROSS REFERENCE TO OTHER PATENT APPLICATIONS

None.

BACKGROUND OF THE INVENTION

(1) Field of the Invention

The present invention relates generally to scoops for measuring the density of fluid in pipelines and, more specifically, in one or more embodiments to novel scoop configurations that provide improved flow and more accurate density readings of the fluid.

(2) Background of the Invention

Scoops have been utilized for decades to monitor the density of the fluids in pipelines. The density of the fluids relates to how much product is transported. Accuracy of the density readings is important because the result can affect the prices paid for shipping product through the pipeline, which prices can be significant. Therefore both the pipeline companies and the users of the pipelines desire to obtain the most accurate readings as possible.

Despite the long felt need for accurate readings, prior art scoops have long had many problems that have not been resolved. Prior art scoops may not produce enough fluid flow to obtain a good sample. In some cases, differential pressure devices such as pumps are required when using prior art scoops. Differential pressure devices can introduce fluid contamination as well as increase the size and complexity of the density measurement systems.

Scoops used to take samples can be inaccurate because fluid beneath the valve is static. Therefore the sample taken may not be representative of fluid in the pipeline at the moment the sample is taken and/or can be contaminated with fluid that has accumulated beneath the valve.

In some cases, scoops are mounted utilizing a threaded receptacle that may be secured and sealed to the pipeline utilizing one of three sanctioned connections 1) pipe threads & sealant; 2) socket weld or 3) butt-weld. The threads in the threaded receptacle provide a seal with the threaded receptacle. However, mounting the scoop to the threaded receptacle can provide difficulties in orienting in the pipe in a manner that maximizes flow through the scoops.

Another problem is that scoops must on occasion be removed from the pipeline to allow pigs to pass through the pipeline. Removing and reintroducing the scoops can be time consuming with corresponding lost use of the pipeline.

Those of skill in the art have long sought a better scoop design and better scoop systems to provide more accurate readings. Consequently, those of skill in the art will appreciate the present invention, which addresses the above and/or other problems.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide improved scoop designs.

Another possible object of the invention is to provide a scoop design that is compact and improves flow of product through the scoop.

Yet another object of the invention is to provide a scoop design that bends a pipe so the pipe remains straight but the face of the scoop is directed laterally into the flow.

Yet another object of the invention is to provide a scoop design utilizing a tubular to pipe connector wherein the pipe connector threads onto a mating threaded connector on the pie but provides a compressible connection that allows rotation of the scoop for orientation of the scoop prior to tightening of the connector.

Yet another object is providing a retractable pipe scoop design.

Yet another object is to provide a compact bi-directional tandem scoop design.

Yet another object is to provide an even more compact single scoop pipe bi-directional scoop design.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention.

FIG. 1A is a front elevational view, partially in hidden lines, of a scoop to obtain a product sample in accord with one possible embodiment of the present invention.

FIG. 1B is a side elevational view, in cross-section, of the scoop of FIG. 1A in accord with one possible embodiment of the present invention.

FIG. 2A is a side elevational view, partially in cross-section, showing the scoop of FIG. 1A and 1B mounted to a pipe utilizing a tubular to pipe connection in accord with one possible embodiment of the invention.

FIG. 2B is an enlarged elevational view, in cross-section, showing a tubular to pipe in accord with one possible embodiment of the invention.

FIG. 3A is a side elevational view, partially in cross-section, showing a retractable scope and yoke design that in a retracted position with respect to a pipeline in accord with one possible embodiment of the present invention.

FIG. 3B is a side elevational view, partially in cross-section, showing the retractable scope and yoke design of FIG. 3A in an extended position with respect to a pipeline in accord with one possible embodiment of the present invention.

FIG. 3C is a front elevational view, partially in hidden lines, showing the retractable scoop and yoke design of FIG. 3A and 3B prior to mounting a threaded connector to the pipe connector in accord with one possible embodiment of the invention;

FIG. 3D is a top view of a yoke component for a retractable scoop in accord with one possible embodiment of the present invention.

FIG. 4 is a side elevational view, partially in hidden lines, showing one type of compact sampling and/or densitometer loop with tandem scoops in accord with one possible embodiment of the present invention.

FIG. 5 is a front elevational view, partially in hidden lines, showing another type of compact sampling and/or densitometer loop with tandem scoops in accord with one possible embodiment of the present invention.

FIG. 6 is a perspective view showing a prover, sampling and/or densitometer loop with tandem scoops in accord with one possible embodiment of the present invention.

FIG. 7 is side view, partially in hidden lines of a first type of bidirectional flow single tubular flow scoop that provides a sampling and/or densitometer and/or prover loop in accord with one possible embodiment of the present invention.

FIG. 8 is a side view, partially in cross-section, showing a second type of bidirectional flow single tubular flow scoop with a mixing chamber in accord with one possible embodiment of the present invention.

FIG. 9A is a side elevational view of wafer mounted tandem scoops that provides a sampling and/or densitometer and/or flow meter loop in accord with one possible embodiment of the present invention.

FIG. 9B is a cross-sectional view of FIG. 9A along lines A-A in accord with one possible embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Detailed descriptions of the preferred embodiment are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or manner.

FIG. 1A and FIG. 1B show a bended scoop design 10 that comprises a single seamless pipe or tubular with first tubular portion 12 adjacent scoop end 14. Second tubular portion 28 has a larger outer diameter 30 than outer diameter 26 of first tubular portion 12.

One possible method of the present invention involves machining the single tubular pipe to reduce the original pipe stock diameter to outer diameter 30 of second tubular portion 28. Then further machining reduces the outer diameter of first tubular portion 12 to outer diameter 26. Shoulder 32 is formed between first tubular portion 12 and second tubular portion 28. The scoop end is then bent as shown to provide scope face 16 that is oriented laterally and preferably perpendicular with respect to centerline 24 as indicated by line scoop face centerline 19.

Accordingly, the bending of first tubular portion 12 of scoop design 10 results in forming scoop face 16. In one embodiment, scoop face 16 provides opening 22 (See FIG. 1A) that is preferably perpendicular and at least angled with respect to tubular centerline 24 as indicated by the perpendicular scoop face centerline 20. At least a portion and preferably the centerline of scoop face 16 is coaxial with a surface of the straight portion of first tubular portion 12. Scoop face 16 comprises outline 36 that preferably defines a plane that is parallel to axis 24. Outline 36 can be elliptical or substantially elliptical in shape. A smaller axis 21 of the ellipse of outline 36 is substantially equal to an internal diameter 38 of scoop design 10. The larger axis of the ellipse varies with respect to the bend radius.

First tubular portion 12 is bent to provide bend radius 18 as shown in FIG. 1B. Bend radius 18 is between two times and four times of scoop 10 and preferably two and four times that of outer diameter 30 of second tubular portion 28 although conceivably between two and four times outer diameter 26 of first tubular portion 12. In another embodiment, bend radius 18 may be between two and three times outer diameter 28. In another embodiment, bend radius 18 may be between 2.3 and 2.7 times outer diameter 28 and/or may be within a smaller range or larger range or outside these ranges. The bend radius may vary depending on the outer diameter of first tubular portion 12. The bend radius affects the fluid flow characteristics and these ranges have been found to provide the best fluid flow through bended sample scoop design 10.

While the features of the scoop face 16 are defined herein in terms of geometrical features such as planes, ellipses, perpendicular, and so forth, it is understood that the features are not geometrically perfect and could have variations, e.g., with 2 and/or to 5 and/or to 10 and/or to 20 range degree variations and any range there between. However, the design may fall outside these ranges and may include corresponding non-linearities.

Scoop 10 provides mark 34 shown in FIG. 1A that is aligned with the center of scoop face 16. This allows alignment of scoop face 16 with respect to the center line of the pipeline as discussed with respect to FIG. 2. In other words, scoop 10 can be rotated to provide that mark 34 is in-line with the axis of the pipeline, whereupon the scoop is fixed in that orientation as discussed hereinbefore.

Scoop design 10 is preferably provided in three different sizes with outer diameter 30 ranging from one inch to one and one-half inches.

FIG. 2A shows the scoop design 10 mounted in an orientable or alignable sampling assembly 200 that permits alignment of scoop face 16 with respect to the pipeline axis and flow arrow 218. In this way, flow or fluid pressure into scoop face 16 can be maximized. Orientable sampling assembly 200 is believed to be yet another significant improvement over the prior art.

Alignable or orientable sampling assembly 200 preferably utilizes tubular to pipe connector 202, which is commercially available off the shelf, in a highly unique manner. As used herein, tubulars do not have threads. On the other hand pipe connectors require threads. Tubular to pipe connector 202 comprises a tubular pipe connection with ferrule seals 218, 220 and threaded pipe connection with threads 208. Accordingly a tubular to threaded connection comprises a connection from a non-threaded cylinder to a threaded connection. Tubular to pipe connector 202 comprises compression nut 204, which is threadably securable to pipe connector 206 utilizing threads 222. Pipe connector 206 provides pipe connection with threads 208 to receptacle 210, which is provided on pipe 212. Receptacle 210 utilizes seal 214 with pipe 212, which can be one of three sanctioned connections 1) pipe threads & sealant; 2) socket weld or 3) butt-weld. Valve 216 may be secured to an upper end of scoop design 10 and may be utilized to provide samples of the pipe fluid as desired.

FIG. 2B shows an enlarged view of tubular to pipe connector 202. It will be seen that compression nut 204 can be utilized to compress ferrules 218 and 220 for sealing around the tubular body of scoop design 10. As compression nut 204 is tightened by rotation on threads 222, a seal is formed, which may be referred to as a first seal in the claims, around the tubular body of scoop design 10. Further, threads 208, which may be referred to as a second seal in the claims, are tightened to provide a seal between receptacle 210 and pipe connector 206. Shoulder 32, shown in FIG. 1A and 1B, seats onto seat 232 formed within tubular to pipe connector 202.

In operation of one embodiment of alignment or orientation, scoop 10 is placed in tubular to pipe connector 202 until shoulder 32 of scoop 10 engages seat 232 in tubular to pipe connector 202. Scoop 10 can then be rotated to orient scoop face 216 within pipe 212 for receiving flow in pipe 212 as indicated by arrow 218. This is accomplished utilizing mark 34 shown in FIG. 1A that is aligned with the center of scoop face 216. Once scoop face 216 is aligned with respect to pipe 212, then compression nut 204 can be tightened to seal around the tubular body of scoop 10. Two scoops like that of FIG. 2A may be used to provide a measurement loop for bi-directional flow out of pipe 212 and then retum the flow to the pipe after measurements are made as discussed hereinafter.

FIG. 3A, FIG. 3B, FIG. 3C and FIG. 3D show aspects of retractable scoop and yoke design pipeline scoop 300 in accord with one embodiment of the present invention. Retractable pipeline scoop 300 preferably utilizes scoop design 10, which allows easy movement into and out of pipeline 304 because scoop design 10 has the same OD as a single tubular. While other types of scoops could possibly be utilized, scoop design 10 is probably the best type of scoop for use in retractable pipeline scoop 300.

As discussed herein with other embodiments of the invention, two retractable pipeline scoops could be connected together to form a flow loop for to measure pipeline fluid with a densitometer, flow meter, prover, and/or takes samples as desired.

Unlike prior art scoops which may be time consuming to remove when a pig is sent down the pipeline, retractable pipeline scoop 300 can be easily retracted from the pipeline and inserted into the pipeline without requiring loss of the seal. Pipeline downtime is therefore greatly reduced.

In this embodiment, upper yoke 305 and lower yoke 304 are mounted on yoke screws 306 and 308. Yoke screws 306 and 308 extend through openings 310 and 312 in overall yoke design 302 shown in FIG. 3D. Scoop 10 extends through but is fixed to opening 314 in upper yoke 305. Openings 311 and 313 in upper yoke 305 are threaded. The corresponding openings 316, 318 are not threaded. Opening 320 in lower yoke 304 allows scoop 10 to slidably move therethrough as seen in FIG. 3A, FIG. 3B, and FIG. 3 c.

Accordingly, one main difference between upper yoke 302 and lower yoke 304 is that openings 311 and 313 are threaded whereas openings 316 and 318 are not. As well, upper yoke 305 is secured to scoop 10 whereas lower yoke 304 allows scoop 10 to move therethrough and includes an O-ring seal when the tubular to pipe connector sealing is not yet connected (See FIG. 3C) prior to operation as shown in FIG. 3A (scoop removed from pipeline) and FIG. 3B (scoop extended into pipeline).

As yoke screws 306 and 308 are rotated, yoke 305 is urged to move. For manual operation, a few turns can be applied to one yoke screw and then applied to the other yoke screw. The operation could be automated.

The sealing of FIG. 2 is utilized during operation as shown in FIG. 3A and FIG. 3B but utilizes O-rings at 320 prior to connection of the tubular to pipe seals as indicated in FIG. 3C. O-rings may comprise suitable resilient O-ring seal material. The O-ring seal preferably utilizes a smoother finish on the scoop pipe surface.

FIG. 3D shows the general plan layout of upper yoke 305 and lower yoke 304 with the differences discussed hereinbefore for openings 310, 312, and 315.

FIG. 4, FIG. 5, FIG. 6, FIG. 9A, and FIG. 9B show various compact tandem scoop configurations that utilize two scoops oriented in opposite directions on a single flange in the pipeline for sampling and/or densitometer and/or flow meter fluid flow loops. The measurement flow loops discussed hereinafter provide sufficient flow of fluid from the pipeline without the need for differential pressure devices (such as pumps or the like), thereby significantly reducing the size, complexity, and fluid contamination. In a preferred embodiment, the compact sampling loops utilize scoop 10 discussed hereinbefore but the present invention is not limited to those scoop designs.

In FIG. 4 there is shown flow axis aligned tandem scoop system 400 mounted to a single flange 406. Scoops 402 and 404 extend through top flange 406, which may be a typical 3″-600# mounting flange. Scoops 402 and 404 are sealed by top flange 406, which itself is sealingly mounted to the pipeline. Flow proceeds through flow loop 416 as indicated by arrows 408, 410, 412, and 414 whereby flow is taken out of the pipeline and then returned to the pipeline. Well known configurations of the flow loop may comprise densitometer 418, sampling valves 420, 422, and flow control valves 424, 426, and 428. As per standard API requirements, scoops 402 and 404 are designed to have a length that access the middle ⅓^(rd) of flow.

In tandem scoop system 400, scoops 402 and 404 are positioned upstream and downstream of each other in line with the axis of the pipe and oriented in opposite directions. Scoops 402 and 404 are mounted into a single flange 405 and secured together at a lower end by mounting member 430. Bends 432 and 433 are provided to allow the various connections to be made to valves 426 and 424. Accordingly, an entire sampling system can extend through a single flange mounting.

FIG. 6 shows a perspective view of flow axis aligned scoops 602 and 604 with connections to densitometer 606 and prover 608. A half portion of pipeline 610 is provided with flange 612 secured to flange mounting 614 provided on pipeline 610. Valves 616, 618, 620, and/or other valves can be used to control fluid flow through the measurement flow loop. Fluid samples can be taken at 622 and 624.

Referring now to FIG. 5, perpendicular mount tandem scoop system 500 provides scoops 502 and 504 positioned side by side or perpendicular with respect to the axis of the pipeline. In this embodiment flange 506 may comprise a 2″-150# mounting flange. Bends 508 and 510 permit connection to flow loop 506, which in this embodiment comprises densitometer 516 and valves 518, 520. Flow may proceed into and out of the pipeline in a direction through flow loop 509 with flow direction indicated by arrows 512 and 514.

FIG. 9A and FIG. 9B show wafer mount tandem scoop system 900. In two possible examples, wafer flange 902 may comprise a 12″ 150# or 10″ 900# wafer flange. The wafer flange can be mounted between flanges in the pipeline so that wafer flange 902 surrounds the flow area going through the pipeline. In this example, scoops 904 and 906 are axially aligned with respect to the pipeline axis and extend from opposite directions and from opposite sides of wafer flange 902. Scoops 904 and 906 are sealed and mounted within wafer flange 902 as indicated at 908 and 910 and are essentially in-line with plane 912 defined by wafer flange 902.

In wafer mount system 200, it is not necessary to provide a bend in scoops 904 and 906. Flow loop 914 can comprise densitometer 916, sampling valves 918, 920, flow meter 926, and control valves 922, 936, 928. Fluid flows through loop 914 in the direction indicated by arrows 928 and 930. As indicated in FIG. 9B, flow proceeds out of the pipeline in the direction shown by arrow 934 and into the pipeline in the direction indicated by arrow 932. Scoop faces 938 and 940 are axially aligned with pipeline centerline 942.

Accordingly, the present invention provides three compact tandem scoop system 400, 500, and 900 that mount two scoops to a single flange.

FIG. 7 and FIG. 8 show bi-directional flow scoops formed within a single pipe. Bi-directional flow loop scoop 700 provides a single tubular scoop that can be utilized to provide a flow loop for density, proving, sampling, and the like as discussed hereinbefore. Bi-directional mixing scoop 800 provides a single tubular scoop that can be utilized to provide a mixing chamber with continually refreshed fluid so that the sample is representative of fluid in the pipeline at the time the sample is taken avoiding the problems of trapped sample at the sampling valve as discussed hereinbefore.

Bi-directional flow loop scoop 700 utilizes single pipe 702 with two separate internal flow paths 704 and 706. The external shape of single pipe 702 is similar or the same as described by scoop 10 discussed hereinbefore so tubular to pipe connector can be utilized for sealing and orientation. Flow proceeds from the pipeline into scoop face 708 as indicated by arrow 710. Fluid then flows as indicated by arrow 712. As indicated by arrow 714, flow goes through a measuring loop, which may be similar to that discussed hereinbefore including a densitometer, prover, sample connections, valves, and the like. Flow then returns as indicated by arrow 716 through tube 718 which enters pipe 702 and is sealed at seal 720. Flow then continues through flowline 706 as indicated by arrow 718 and exits back into the pipeline through opening 722 as indicated by arrow 720. The sealing can be the same as discussed hereinbefore with respect to FIG. 2 utilizing a compression nut that allows orientation of scoop face 708. Bi-directional scoop 700 could also be utilized with the retractable yoke design 300 discussed hereinbefore to provide a retractable bi-directional measurement flow loop.

FIG. 8 provides a single pipe bi-directional scoop 800 that provides a mixing chamber 802 which is continuously refreshed. Prior art sampling systems that utilize a scoop suffer from the problem that stale fluid accumulates therein. Thus, fluid taken at a particular moment may not be representative of fluid in the pipeline. Since the samples are often timed, this could be problematic in verifying that the sample is valid.

Scoop 800 is comprised of single pipe 804. Scoop 800 may be sealed/oriented as discussed with respect to FIG. 2A and FIG. 2B as discussed with respect to FIG. 7 or using other seals as desired. Fluid enters scoop face 806 from the pipeline as indicated by arrow 812. The fluid travels up flow path 808 and enters mixing chamber 802 as indicated by arrow 814. The fluid in mixing chamber 802 is thereby continuously refreshed. Fluid exits mixing chamber 802 via tube 820 and flows in the direction of arrow 816 through flow path 810. Fluid exits single pipe 804 as indicated by arrow 888 through opening 822.

Accordingly, the present invention provides a highly desirable scoop design 10 as indicated in FIG. 1A and FIG. 1B, a seal and orientation apparatus as indicated in FIG. 2A and FIG. 2B, a retractable scoop design shown in FIG. 3A, FIG. 3B, FIG. 3C, FIG. 3D, compact single flange bi-directional tandem mounted scoops as indicated by FIG. 4, FIG. 5, FIG. 6, and FIG. 9A, and single pipe bi-directional scoops as indicated by FIG. 7 and FIG. 8.

The foregoing description of the preferred embodiments of the invention has been presented for purposes of illustration and description only. It is not intended to be exhaustive or to limit the invention to the precise form disclosed; and obviously many modifications and variations are possible in light of the above teaching. Such modifications and variations that may be apparent to a person skilled in the art are intended to be included within the scope of this invention as defined by the accompanying claims. 

1-20. (canceled)
 21. A retractable sample scoop mountable to a pipeline for taking samples from the pipeline, said pipeline comprising an opening in a pipeline wall for taking said samples, comprising: a retractable mounting mechanism attachable to said pipeline wall; a tubular supported by said retractable mounting mechanism, said tubular comprising a first tubular portion adjacent a scoop end, said tubular defining an internal bend at said scoop end leading to a face with an opening for said samples, said tubular being extendable into said opening of pipeline and retractable from said pipeline; and a first seal for said retractable mounting mechanism operable to seal off around said first tubular portion with respect to said pipeline while permitting insertion, retraction and rotation of said first tubular portion with respect to said pipeline; and a second seal which comprises a tubular to pipe connector.
 22. The retractable sample scoop of claim 21, wherein said second seal comprises a non-resilient seal.
 23. The retractable sample scoop of claim 21, comprising a plurality of supports extending from said retractable mounting mechanism, a second tubular portion distal said scoop end, a movable yoke that is secured around said second tubular portion, interconnections between said movable yoke and said plurality of supports operable to permit movement of said movable yoke with respect to said plurality of supports and said pipeline.
 24. The retractable sample scoop of claim 23, wherein said interconnections comprise threaded interconnections whereby rotation of said supports controls said movement of said movable yoke with respect to said plurality of supports.
 25. The retractable sample scoop of claim 24, wherein said tubular to pipe connector further comprises a fitting operable for sealingly mounting to said pipe line, said first tubular member being movably extendable through said fitting, a connector on said moveable yoke for connecting to said fitting when said first tubular is fully or substantially inserted into said pipeline.
 26. The retractable sample scoop of claim 25, wherein said first seal comprises a fitting with a resilient seal, which seals between said fitting and an outer surface of said first tubular member.
 27. The retractable sample scoop of claim 26, wherein said retractable mounting mechanism comprises a plurality of supports, and a fixed position yoke secured to said fitting and said plurality of supports.
 28. A method for making a retractable sample scoop mountable to a pipeline for taking samples from the pipeline, said pipeline comprising an opening in a pipeline wall for taking said samples, comprising: providing a retractable mounting mechanism that is attachable to said pipeline wall; supporting a tubular with said retractable mounting mechanism; providing that said tubular comprises a first tubular portion adjacent a scoop end leading to a face defining an opening for said taking of said samples; providing that said tubular defines an internal bend at said scoop end; providing that said tubular is extendable into said opening of pipeline and retractable from said pipeline; and providing a first seal for said retractable mounting mechanism operable to seal off around said first tubular portion with respect to said pipeline while permitting insertion, retraction and rotation of said first tubular portion with respect to said pipeline; and providing a second seal which comprises a tubular to pipe connector.
 29. The method of claim 28, further comprising providing that said second seal comprises a non-resilient seal.
 30. The method of claim 28, comprising providing a plurality of supports extending from said retractable mounting mechanism, securing a movable yoke around that a second tubular portion distal said scoop end, providing interconnections between said movable yoke and said plurality of supports operable to permit movement of said movable yoke with respect to said plurality of supports and said pipeline.
 31. The method of claim 30, comprising providing that said interconnections comprise threaded interconnections whereby rotation of said supports controls said movement of said movable yoke with respect to said plurality of supports.
 32. The method of claim 31, comprising providing that said tubular to pipe connector further comprises a fitting operable for sealingly mounting to said pipe line, said first tubular member being movably extendable through said fitting, and providing a connector on said moveable yoke for connecting to said fitting when said first tubular is fully or substantially inserted into said pipeline.
 33. The retractable sample scoop of claim 32, wherein said first seal comprises a fitting with a resilient seal, which seals between said fitting and an outer surface of said first tubular member.
 34. The retractable sample scoop of claim 33, wherein said retractable mounting mechanism comprises a plurality of supports, and a fixed position yoke secured to said fitting and said plurality of supports. 